Immune Regulatory and Underlying Mechanisms of Polysaccharides from Aronia melanocarpa Fruit by Integrated Analysis of Multiple Endogenous Metabolism

The fruit of Aronia melanocarpa (Michx.) Elliott is a berry with multiple properties and was included as a new raw food material by the National Health Commission of China (NHC) in September 2018. This study focused on the immune regulatory properties and underlying mechanism of polysaccharides extracted from Aronia melanocarpa fruit (AMFP) by undertaking an integrated analysis of multiple endogenous metabolic pathways. An improvement in AMFP in immunosuppressed model mice at three levels of immune organs, immune cells, and immune factors was determined. The immunomodulatory role of AMFP was assessed through measurement of metabolomic and lipidomic profilings by UPLC-Q-TOF/MS. A total of 53 differential endogenous metabolites in the urinary, serum, and lipid metabolomics were identified, followed by KEGG pathway enrichment. Furthermore, the underlying mechanisms were elucidated by an integrated analysis of multiple metabolomics and lipidomics. Primarily, we found regulation of immune-related metabolic pathways, including nicotinate and nicotinamide metabolism, sphingolipid metabolism, glycerophospholipid metabolism, purine metabolism, steroid hormone biosynthesis, and arachidonic acid metabolism. The results also demonstrated the mutual validation of key pathways and mechanisms. AMFP potentiated both humoral and cellular immunity responses and protected the immune system from oxidative damage. This research provides a reference and a basis for the development and application of AMFP in the field of health foods that regulate immunity.